With the popularization of a great variety of electronic devices such as a smart phone, a tablet personal computer (tablet PC), a portable multimedia player (PMP), a personal digital assistant (PDA), a laptop PC, and a wearable device, there is an increasing interest in developing a technique for a simple payment method using such electronic devices.
In response to this growing interest in a simple payment method, various techniques for a simple payment method are being developed. One of such techniques is for a simple payment method based on recognition of a bar code output on a display of the electronic device.
Another technique is a simple payment method using communication with a payment terminal (often referred to as a point of sale (POS)) through a short-range communication module included in the electronic device.
Still another technique for a simple payment method is to use what is called a magnetic stripe transmission (MST) signal. Typically, the MST signal is a magnetic field signal usually generated by passing (e.g., swiping) a payment card (e.g., a credit card, a debit card, a check card, etc.) through the payment terminal. According to this technique for a simple payment method, the electronic device itself outputs the MST signal such that the payment terminal can recognize the output magnetic field.
In case of the latter technique, because the electronic device outputs the MST signal that is the same as the magnetic field signal generated when the payment card is passed through the payment terminal, it is available for use with an existing payment terminal without the need for any additional device. For this reason, this technique is becoming widespread.
However, a problem with this simple payment technique that outputs the magnetic field signal is that a malicious third party may possibly acquire the magnetic field signal transmitted to the payment terminal. In this case, a certain malicious third party may perform payment using the acquired magnetic field signal within a validity period.